Spray gun



May 1, 1951 c. w. TRAUGHBER, JR

' SPRAY GUN 2 Sheets-Sheet 1 Filed Jan. 13, 1948 FIG. I.

Pa: CHARLES 144 M40 @Wf'm A TTORNE Y May 1, 1951 c. w. TRAUGHBER, JR

SPRAY GUN 2 Sheets-Sheet 2 Filed Jan. 13, 1948 w m w Y J 4 2 7- a a a 71n 7 5 I 1 2 ZI .H Mm 7 3 M743 INVENTQR. CHARLES W. TRAUGHBER, JR

Arron/var Patented May 1, 1951 UNITED STATES ATENT OFFICE 4 Claims. 1

' -'I'hisinvention refers to s raying equipment and more particularly toa spray gun for use in. mixing materials with a pneumatic pressureagent, for discharging the materials under pres-' sure, against asuitable surface close'by, tocover it with a film or coating of thematerials.

The'conventional type of spray gun used commercially for industrial ordomestic use, uses air under pressure to carry liquid or powderedmaterials in the stream discharged from its nozzle. The materials areinjected into the discharge stream by the suction of the pressure airstream. If the nozzle becomes choked up, the pressure from the air tendsto act inside the nozzle and against the container from which thematerials were intended to be sucked. If the discharge from the nozzleis impeded in any way, the suction action on the materials is decreasedin proportion. This causes a less satisfactory discharge and theefiicacy of the spray gun is substantially diminished. The suctioninduced by the air stream affords an indirect pressure on the materialsto be applied. It acts only on the surface of the top ingredients heldin the container, its mixing action thereon is not as satisfactory aswould be desired, unless of course the original materials are relativelylight, uniformly distributed in the container and of the same specificgravity. This is seldom the case. pulled up to the nozzle in a morecompact state than they would if they were blown up from behind. Thepressure air stream also has to use up a great part of its energy indrawing up the materials to the nozzle before mixing them with the air,prior to the discharge through the nozzle. In order to overcome theseand other objections it is the object of this invention to provide a newand improved spray gun that will avoid one o'r'more of the disadvantagesand limitations of the prior art.

Another object of the provide a new and improved spray gun that willemploy pneumatic pressure to directly injectappliable materials into.the gun as well as cause the mixture and discharge therefrom.

An additional object of the invention is to provide a new and improvedspray gun that will have a self cleaning action and have all parts andpassages subject to the spraying maneuvers of the materials and airpressure, continuously swept by the air currents employed while in use.A further object of this invention'is to provide a new and improvedspray gun having a balanced pressure of air and materials to be atomizedduring the spraying operation; to have Besides the ingredients arepresent invention is to 2 q adequate adjustment for control of the airpressure and materials, and a variable arrangement for controlling thetype of spray, as well asuse its air pressure more eifectively.

It is an additional object of this invention to provide a swirlingmotion ofair and materials. in

the mixing chamber nozzle to break up any small. lumps of materialcollected therein.

A further object of the invention is to provide a new and improved spraygun having its nozzle cushioned on the inside by the air spray to reduce\the wear of the abrasive "passing therethrough.

Other objects will become apparent as the in'! vention is more fully setforth.

For a better understanding ofthe invention, and the objects thereof,reference is made to the accompanying drawings, and the following de-'scription. These together, describe a particular form of the inventionby way of example, while the claims indicate the scope'thereof.

In the drawings:

Figure 1 is a plan view of a spray gun embodying this invention;

Figure 2 is a side elevation of Figure 1, with parts broken away to showits construction, and with a diagrammatic view of the feeding mechanism;r

Figure 3 is a rear end view of Figure 1;

Figure 4 is a sectional view taken along lines 4-4 of Figure 2';

Figure 5 is a sectional view taken along lines 5-5 of Figure 2;

Figure 6 is a sectional view taken along lines 6--6 ofFigure 2;

Figure 7 is an exploded view of the spray end of Figure 2;

,Figure 8 is a front, elevation of the disc, and

Figure 9 is an end view 'of the disc looking in the .direction of arrows9-9 of Figure 8. f Similar reference 'characters'refer to the-same partsthroughout the drawings. In the particular form of the invention shown,a'spray' gun consists'of a hollow handle It, including a passage Hlongitudinally disposed therein and connecting at its upper end with apassage 9. A fitting I2 is provided at the butt of the handle forattaching a pneumatic hose thereto. The projections I3 and M on thefront and back of the handle are termed grips to permit the handle to beconveniently handled. A boss I 5 threaded interiorly for an adjustingscrew 16 controls the travel of a trigger I 'I pending from the portionI 8 of the barrel 22"attached to the handle {'ID at approximately rightangles thereto.

A plug 59 closes up the passages 9 and H and serves as a cap. This plugl9 allows access to the interior of the passage 25 that runs through thebarrel 22 at the top of the passage 9, which it is connected to at rightangles. The rear end of the barrel 22 is provided with an adjustingscrew ill for regulating the amount of air passing through the spray.Usually the line 5! can be left open and the amount of material sprayedfrom the gun is controlled by the adjusting screw 51. The screw can beused to close off the air supply. Packing nut 95 supports the adjustingscrew 9|, and packing 92 prevents leakage from the passage 25. The frontchamber portion 2| of the barrel 22 is extended downwardly from thebarrel 22 at right angles and has its passage 23 depending downwardly atright angles to'the end of the passage 29 and is of the same generalsize. All these passages are preferably circular in cross-section. Anoutlet 24 extends transversely through the wall of the chamber portion2i into the trough 25 provided in thread-portion 55. A retaining nut 26screws on to the exteriorly screw threaded periphery of the portion 55and holds a tapered mixing outer nozzle 2'! thereto by its flange 28 andagainst the disc 29 set in the union recess 35. The outer nozzle nose 5!has an axial threaded orifice 82, which is adjustably andinterchangeably screw threaded therein. An inner nozzle 34 extends intothe mixing chamber 35, in

the outer nozzle 21, from the front wall 36 of the chamber portion 2|.

This inner nozzle 34 has a tapered exterior surface 31 having-holes 38drilled therethrough at an angle of about 45. gular sprays of materialinto chamber from the axial passage 35 in the spout 34. The interiorlyscrew threaded head 46 on the sleeve serves as a spacer and clamps thedisc 29 to the inner nozzle 34 whichis arranged. radially in the groove4| inits periphery. The sleeve ill passes transversely through the Wallsof the portion 2! and is clamped thereto by the head 44 and the stuffingbox cap 42. The interior 15 of the sleeve 40 is of larger diameter thanthe passage 39 and has a piston is travelling in itto close or open theinlet port 55 in the wall of the sleeve. The

inlet port 55 is preferably of rectangular form with its longest portionrunning longitudinally with passage 75. The piston rod 55 reoiprocatesthe piston 53, and projects through a slot Tl, in the trigger H, and isadjustably positioned in a collar or adjuster #8. A piston rod 79 isconnected to the other end of the adjuster l8 and operates anotherpiston 55 in a cylinder i! installed transversely in the handle [0 andheld therein by the head 48 and stufiing box cap 49. The coil spring 50keeps the pistons under tension through the aid of cap 8'5 and tendingto close the ports 55, and 95, which respectively allow the materialsand air pressure streams to pass into the mixing chamber of the nozzlethrough the passages 38 and 25. The ports 55, and 9-5 are preferably ofrectangular form like port 45 to give better support to the pistons 53and 56. A stop 8'! is positioned on rod i9 to limit its travel. Thematerials are introduced through the passage 85 by a hose 59 attached tothe fitting 52- which is screwed to the chamber portion 2! and thenthrough the port 35, interior l5, passage 39 through holes 38 intochamber 35. The air enters through the passage-ii and passes throughtheports 55 and 95 into passages Sand 25- 50 23 then through slots 5'!into chamber 35. The pis ton rods 45 and Fe-are operated by the triggerThis is to provide anl1 acting on the adjustable nut 18 as the triggeri1 is pulled by the hand of the user. The trigger is preferably of thechannel construction shown in the drawings. The disc 29 has slots 57 setout radially therein and bevelled oppositel to cause a diversion of theair pressure stream coming therethrough into an angular plane.

The operation of the device is as follows. It is assumed that a hose 54is attached to the fitting l2 and provides air at 60 p. s. i. from anair feed line 82. A second air line 83 is connected to the air feed line82 at one end and the other end is connected to a material tank 85 tomaintain the same air pressure in the tank as is placed on the spray gunand to stir the tank materials. A hose 5! is attached from the upper endof the material tank tothe inner nozzle 35 at 50 p. s. i. A valve 85controls the air supply to the bottom of tank 85. An air bleeder 93 isattached to the tank 84 and through its valve 55 controls the escape ofair from the tank. The amount of escaping air is approximately 1 to 2cubic. feet per minute during the time the materials are mixing. Watermixed material. are supplied to the tank 54 through the hole covered bycap 60.

The operator holding the handle 15 pulls the trigger l1 backwards so thepiston 55 will open the ports 55 and 95 in the handle and upper passage9 so the air pressure stream will start passing through slots 5'! indisc 28 into the mixing chamber 35. An instant later the port 45 opensand allows the materials to be forced through the inner nozzle 34 intothe mixing chamber-35i 'As' the trigger I1 is pulled over more and movesthe pistons 43 and 56 to open the ports more, it unthrottles the streamsof air and materials. The full pressures of each cause the air passingat an angle through the slots 51 in the disc 29 to mix with thematerials ejected under pressure into the chamber 35 at an angle witheach turbulently and/or cyclonically combining therein, before passingthrough the interchangeable orifice 32 on its way to be used on thesurface to be sprayed. When the trigger I! is released, its pistons 53and 55 pass over the ports 45, 55 and 95 and close them. The airpressure stream asses through the slots 51 in a turbulent and/orcyclonic manner which prevents the material from sticking on the wallsof chamber 35. The stream continues through the chamber 35 as it bouncesfrom the wall towards the axis of the chamber and combines at the end ofthe inner nozzle 34 with the angular squirting of materials through theholes 38, under pressure. This mixture is further concentrated in theconverging poriion. of the chamber 35 and flows through the orifices inthe screw orifice 32 at high speed and thoroughly mixed. The purpose ofthe initial opening of the ports 55 and 95 by the piston 56 before thatof the port 55 by the piston 43 is to anticipate the lag .due to thegreat distance through the passages ll, 5, 20 and 23,

in the handle and barrel that the compressed air from the passage H hasto pass through before reaching the mixing chamber 35. Thus the main airstream from the hose 54 is flowing into the chamber 35 at approximatelythe same time as the materials with its air stream carrying theparticles arrive in the chamber 35. Both main air stream and materialsmix in a cyclonic manner under their respective pressuresand coordihate-with each other without any loss of energy. The particles arethrown with considerable kinetic energ into the chamber 35 which isboostedby the air stream from the hose 5% connected to the passage H. iThe mixture is enhanced by the angular spread out streams of air throughthe slots 51 in the disc 29 as they bounce against the chamber walls andthe surfaces of the inner nozzle 34. As the streams pass through theholes 38 with their air and particles of materials rushing through withconsiderable violence, the turbulent and/or cyclonic air streams comingthrough slots 57 are intermixed and break up the particles of thematerials so they are evenly spread throughout the streams and rush outof the orifice 32 fully mixed and at high pressure.

The thorough mixture of the materials within the balanced pressurizedstreams prevents any tendency to create open spots or areas duringdistribution of the spraying materials against the surface beingtreated. The spraying becomes clear cut and the application of thematerial can be controlled from a fine film to a heavy coating. Thevarious adjustments enable the gun to be accurately arranged for anywork within the scope of its duties, and the arrangement of the passagesand parts permit facile inspection, cleaning and replacement, of parts.

While but one general form of the invention is shown in the drawings anddescribed in the specifications, it is not desired to limit thisapplication for patent to this particular form, as it is appreciatedthat other forms of construction could be made that would use the sameprinciples and come within the scope of the appended claims.

Having thus described the invention, What is claimed is:

1. A sprayer including a main body having a pair of spaced-apart andco-axial chambers thereon, passage means for admitting compressed 'fluidto one of said chambers through a port opening therein, passage meansfor admitting spray liquid to the other of said chambers through a portopening therein, a piston in each of said chambers controlling each ofsaid port openings, a pair of aligned piston rods connected to'saidpistons, means for adjustably connecting said piston rods together, atrigger pivoted on said main body, said trigger having an opening toallow passage therethrough of the adjustable means for said piston rods.

2. A sprayer as set forth in claim 1, wherein the piston controlling theport opening for the admission of compressed fluid, opens the said portopening prior to the opening by the other of said pistons of the portcontrolling the spray liquid.

3. A sprayer as set forth in claim 1 in combination with means foradjusting the normal position of the trigger and maintaining it in suchadjusted position.

4. A sprayer as set forth in claim 1, said sprayer having a handle gripand said trigger having means for adjusting its normal position, saidmeans comprising an element secured to said grip and a screw threaded insaid handle grip.

CHARLES W. TRAUGHBER, JR.

REFERENCES CITED The following references are of record in the file ofthis patent:

' UNITED STATES PATENTS

